The invention relates to a lifting device, particulary for a dentist chair, with support arms arranged in scissor form between a base portion and a height-adjustable support portion, joined together by an axle, which arms are arranged spaced and parallel to each other in pairs, the one ends of which are articulated at a fixed part, while the other ends are articulated at the movable part of a horizontal guide of the base portion, on the one hand, and of the height-adjustable support portion, on the other.
A lifting device is known for example from U.S. Pat. No. 3,522,925. There, however, the lifting device is designed as a double scissor arm construction with double scissor arms arranged on either side of the chair and connected together by joints.
Such a lifting device is expensive to construct and has relatively many bearing points which, for sufficient stability, must be very precise and are therefore expensive to manufacture. Another disadvantage is attributed to the fact that the scissor arms do not fold to an extreme depth.